Update node version

Author: jeromewu

.github/workflows/main.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        node_version: ['12'] #['8', '10', '12']
+        node_version: ['16'] #['8', '10', '12']
         os: [ubuntu-latest] #[ubuntu-latest, windows-latest, macOS-latest]
 
     steps: